Legacy 1.2.x version uses the Avalon tools and Merlin Container created by Apache's Avalon project.
Stability: successfully used in production
Modularity: component oriented using Plexus container (integration with LDAP or DB can be easily done via users-manager and storage API)
Most of classical IM functions are supported: message, presence, roster, subscription, vCard, offine storage, oob (lan file transfer), browse and search.
Server to Server communications
Secure connections via SSL
Message logger and recorder (for statistic usage or supervision)
Email: alag (a) codehaus.org